Batteries can be used for a variety of applications such as portable electronics (cell phones, personal digital assistants, music players, video cameras, and the like), power tools, power supplies for military use (communications, lighting, imaging and the like), power supplies for aerospace applications (power for satellites), and power supplies for vehicle applications (hybrid electric vehicles, plug-in hybrid electric vehicles, and fully electric vehicles). The design of such batteries is also applicable to cases in which the battery is not the only power supply in the system, and additional power is provided by a fuel cell, other battery, IC engine or other combustion device, capacitor, solar cell, etc.
In solid state thin film batteries, those knowledgeable in the field have attempted to build multi-layer, or stacked solid state batteries, but have been limited to only a few stacked cells due to manufacturing problems. This is evidenced by the fact that to date, only miniature solid state batteries have been commercialized for use on credit cards or RFID tag. Those skilled in the art have been unable to manufacture thin film solid-state batteries useful in replacing conventional technology, particularly those batteries for extended use in consumer electronics or in automobiles.
As applications continue to require greater power and efficiency from energy sources such as these batteries, techniques for improving solid-state thin film battery devices continue to be highly desired.